Rivaroxaban was found to be as effective and safe as warfarin in resolving post myocardial infarction (MI) left ventricular (LV) thrombus at three months, according to a Late-Breaking Clinical Trial presented at ACC.25 in Chicago.

The open-label trial, conducted at a single site in Pakistan, randomized 261 patients (54.5 years old on average, 79.3% men) with acute LV thrombus to either rivaroxaban (n=171) or warfarin (n=90) for three months. Of the patients, 90.4% had a STEMI and 9.6% NSTEMI, and 85.1% had undergone PCI. The LVEF was ≤35% in 93.9% of the patients. Patients were treated with dual antiplatelet therapy for one month and then a single antiplatelet therapy for the remaining eight weeks along with an oral anticoagulant.

Results showed that at one month more patients in the rivaroxaban arm had LV thrombus resolution (33 patients [20.1%] vs. seven patients (8.3%) in the warfarin arm (risk difference [RD], 11.8%; odds ratio [OR], 2.41; p=0.017). At three months, LV thrombus resolution occurred in 95.8% of patients in the rivaroxaban arm and 96.6% of patients in the warfarin arm (RD, –0.8%; OR, 0.98; p=0.88).

Secondary endpoints were comparable between the rivaroxaban and warfarin arms, respectively, including all-cause mortality (3.5% vs. 3.3%), ischemic stroke (3.5% vs. 1.1%) and major bleeding (2.3% vs. 1.1%). Follow-up ended at three months when the study was discontinued due to lack of funding.

According to the researchers, there was no evidence of excess harm in regard to morality, ischemic bleeding or major bleeding.

"These findings support the use of rivaroxaban as a viable alternative to warfarin for the treatment of left ventricular thrombus in post-heart attack patients," said principal investigator Jehangir Ali Shah, MD, FACC. "Compared with warfarin, rivaroxaban offers predictable dosing and eliminates the need for routine blood tests to monitor clotting time."

Keywords: ACC Annual Scientific Session, ACC25, Myocardial Infarction